Newbie questions
 

Well Im new to the whole eco tuning, and im weaning off of performance tuning. I just bought a ford focus 2.0l zetech with a 5 speed. I bought this car because the engine has solid lifters so I can really lug it around at low rpms. Now im not hardcore about mileage, I still go full throttle on a regular basis BUT I drive to hours each way for my weekend commute and I will be driving 80 miles per day to school next year.

Here's my question- do cold air intakes really improve my mileage? And what about a less restrictive exhaust or headers? Basically, I want to mod my car in a way that won't effect the looks or hurt performance (if it makes it faster thats fine by me, but give me a 10-15% increase in mileage. My first mod will be a block heater.

Also, what do you guys think of those pulse plugs? (the spark plugs with capacitors) they run $50 a piece, so if they are a scam I would like to know lol.

Cold air intakes hurt mileage, if anything. Intake restriction does not matter at part throttle. Backpressure does hurt economy, but if your system does not choke at full power, it is probably fine in the economy range. There's a pulse plug thread around here somewhere, and lots of other good advice about how to drive for economy. Welcome to the lighter side of life.

ChillyBear -

Welcome to EM! I agree with Bob. Here is info on the pulse plugs :

http://ecomodder.com/forum/showthrea...work-4020.html (no)

I sent a set to another Saturn S-Series owner, and they *fell apart* on him in less than a mile.

CarloSW2

How so?

So you're weaning off of performance tuning, but still feel the urge to gun it every once in a while, eh? That's me, too. It's interesting to note that the engine can withstand that kind of acceleration. SRI/CAI's are said to reduce pumping losses that are common in mass produced stock airboxes of the restrictive sort. Don't know about the percent of increase that your car will experience, but basically a larger diameter exhaust pipe (Depending on your car and application. On a naturally aspirated, mostly stock engine you don't want to go too big.) than your current one, granted that it's restrictive by design, can yield MPG gains through exhaust scavenging. This also reduces pumping losses (like a CAI or SRI) so that the engine doesn't have to work as hard to remove exhaust gasses (on top of everything else) that might've recirculated due to a high backpressure. I would look into the header, but only if you have enough money and patience to tune it soon after. I'm sure there's a way to have it biased towards fuel-effeciency rather than raw power with a stand-alone engine management system. But anyway, there are guys here who make it their goal to attain the highest MPG's possible. They'll be able to give you more insight on how to reach your goals. My info is from a more performance-oriented outlook.

A cold air intake only helps you get more air into your engine at wide open throttle, at cruising speed it is going to give the engine more air then it needs and thus the engine is going to dump in more gas then it needs.

Your exhaust pipe and muffler are not a duct to get the exhaust to the back of the car, larger is not better, people who say it's best to go a step bigger are bad at math as the exhaust flow in your exhaust system is coming out of the engine in pulses, there for the exhaust system needs to be tuned for those pulses, again if you are running wide open all the time that is going to shift to a larger pipe but at normal driving speeds to large of an exhaust pipe is going to de-tune your engine and make it work harder.

For your long drives you might look in to smoothing out the underside of your car.

Buy a scangage-2, it will teach you how to get more mpg, i promise! then as said, a bellypan, next tire change go with a low rolling resistance tire, look at mirror delete/reductions, exaust velocity is higher with a smaller pipe (better for low rpm where the mpg's are, if manul trans shist at 2000 rpm, time traffic lights, coast when possible, stay under 60mph, tap the tremendous resorces on this site, there are people that are expert at almost every aspect of a vehicle, and wecome.

Ah, so what you're telling me is that the car will add more fuel to the air ratio to even it out and consume more gas? I don't think the amount would be significant enough to cause a drop in fuel-efficiency. Plus, I mentioned pumping losses as an explanation for the alleged increase in MPG's that performance companies claim from their products. "Work is work," so if the engine has to "work" to get the air in, it's going to have to rev higher to do so. Don't you want to make it easier for it to do it's job?

Since you're calling me out on my math by saying that, I'm gonna call you out on your spelling. (And logic.) An engine is literally an air pump, so your first line is completely wrong. The exhaust is the medium through which gasses flow out into the atmosphere, unless of course you have an open-header setup, which is very polluting and illegal. These "pulses" are an expression of the lapses between the release of gasses from the exhaust valves. A slightly larger diameter pipe will create a more free-flowing outlet for the exhaust charge that helps scavange those gasses after each "pulse." (The opening of the exhaust valves) While the valves are closed, a vacuum of sorts is created, keeping the stream steady and constant. So to "tune" your exhaust system, that would mean upsizing the piping. The stock pipes are made restrictive for several reasons, but as it pertains to this discussion, their design is done with cost-effectiveness and mass production first, rather than top engine performance. As I said in my previous post, a restrictive exhaust system forces the engine to do extra work. High backpressure can cause recirculation of freshly released gasses, which is not a good thing. As mentioned above, (Not my post) the velocity will be higher in a smaller pipe, but it's a constant battle to keep the charge continually flowing through because it's such a small outlet. Bump the pipe sizing up liberally and the exhaust will flow freer in both the open and closing cycles of the valves more efficiently. For the record, I make WOT runs with a stylish factory exhaust all the time and know dudes with aftermarket exhausts that aim for top MPGs. "Detuning" the engine is only possible through a standalone engine management system which could potentially cause that, if you make a mistake. I guess what you're referring to is the guys with exhausts too big for their cars. That's also a bad thing, because there's simply too much room to create a significant charge in the exhaust stream, leading to less flow. If only they knew.

That's a novel idea, but what can you use that'll go under there?

BTW, this is off-topic, I'm sorry, but that's a really cool profile pic you've got there.

"Ah, so what you're telling me is that the car will add more fuel to the air ratio to even it out and consume more gas? I don't think the amount would be significant enough to cause a drop in fuel-efficiency. Plus, I mentioned pumping losses as an explanation for the alleged increase in MPG's that performance companies claim from their products. "Work is work," so if the engine has to "work" to get the air in, it's going to have to rev higher to do so. Don't you want to make it easier for it to do it's job?"

The air pump can't tell the difference between manifold restrictions and throttle butterfly. At part throttle, their relative percentages are irrelevant. Real ecomodding is a lot cheaper than performance work in some areas. What's the length of a tuned exhaust at maximum mileage? Can pulses get through the close-coupled cat, anyway?

If warm air can carry enough oxygen in for the power required, it will flow easier, and vaporize the gasoline better. Presumably, except in open-loop, near wide open throttle, the injectors will keep the mix lean, just enough for good ignition. See the "warm air intake" threads. (WAI)

I'm pretty sure that's exactly what he was referring to.

This discussion is basically endless, no matter where you go. There's always a bunch of people who heard from someone else who was told by some other guy that this way or that way was better, and very few of them have any background or math/science to back any of it up.

While it's refreshing to see that someone else understands the difference between "bigger" and "too big", it's also a burden to see, yet again, the term "back pressure" come into play.

Ok,
CAI=worse mileage
Headers=debatable
I may try the belly pan, but I wanna do some before and after tests because I don't want it to cause lift (my old car would lift after about 100mph-VERY SCARY).

The only way a belly pan should cause lift is ground effect compression, where the quantity of air that goes under the vehicle can't accelerate quickly enough and "piles up" under the car.

Other than that, it should actually create a lower pressure zone under the car that will induce negative lift, albeit a small amount, due to the acceleration of flow that isn't obstructed.

Re: Pulse plugs... this is anecdotal, but Tim (Daox) had them and mentioned to me just this week he was starting to get a misfire after a relatively low number of miles on 'em. (Maybe he posted about this, I haven't been around as much as usual this week.)

Anyway, he yanked them and installed some Bosch plugs. Problem solved.

yeah, I read a thread about that. Sounds like more headache than the gain is worth.

What "air pump?" You mean the intake system? My Sentra's intake has two sensors: a Mass Airflow (MAF) and an Intake Air Temperature (IAT) Sensor. Both have very relevant significance as to how the car will run. If the MAF craps out, my car will go into "limp mode" as a precaution and won't go past 2K- 3K RPM and the IAT regulates idle at start-up. And if you mean to tell me that reducing pumping losses yields "relatively irrelevant percentages" then the same could be said about keeping a restrictive airbox, so as to keep the air-to-fuel ratios leaner. Guess my $45 cone filter replacement isn't a bargain. You asked what the perfect length would be for a fuel-economy oriented. Please note that a stock cat won't contribute enough backpressure (Barely +/- 0.5 PSI) to warrant a replacement, unless you want a high-flow type, (To make way for a monster turbo setup) but those aren't as effecient at controlling emissions than the former. The ideal setup would be as I just said: a larger diameter pipe, not too big, to allow for more exhaust scavenging, reducing pumping loses and maintaining a constant stream in both the open and close cycles of the exhaust valves. Personally, I don't want to attract too much attention, so when I put one on mine, you better believe I'm investing in a resonator. (If it's not included)

There seems to be a rebellious spirit against the establishment of aftermarket performance parts amongst some of the members here. While those companies may jack up their claims to get a stronger base, their products are results of research and development, as well as actual customer usage in various places, (Street, track, top MPG tourneys, etc.) for the most part. (EFI throttle body spacers not included in my ex.) Maybe it's not even them that rubs dudes like you the wrong way. Could be the stereotypical rice-doucher image that plagues your head. (Thanks, makers of "Fast & the Furious.") Either way, the same proven aftermarket replacements of intakes, exhausts, headers, etc. could definitely be used to achieve more MPG's, aside from HP. Most tuners I know love boasting their highest miles-per-tank. It's very common in Sentra, Fit and Civic forums, which I frequent. It's not all about power.

I'm gonna see this WAI thread that you speak of. You can't seriously be putting in one of those for a leaner A/F ratio. I wouldn't feel too comfortable with my car running leaner than it already does from the factory. (14.7 or so) In the event that you do need to run in open-loop, acceleration will surley suffer. How hot do you want your engine to operate, anyhow?

Internal combustion engines, being of the adiabatic sort of beast family, are inherently more efficient when they're "soaked" closer to combustion temp. The hotter intake air is proven to be more efficient per volume of intake because there is less tendency of the combustion heat to soak into the engine (the engine has already reached equilibrium with the intake air, so less heat is pushed into the metal on combustion because of the already higher cylinder wall temp), and less energy from heat necessary to increase the temperature of the intake volume.

There have been published studies which show these, and other examples, as benefits of increased engine temperature and intake air temperature, where efficiency is concerned.

To clarify the term - Efficiency, in this case, is the amount of energy derived from an amount of fuel during combustion, compared to the actual energy content of the consumed amount of fuel.

The WAI in general doesn't lean the A/F ratio - it reduces the dynamic displacement of the engine, and reduces pumping losses. A less viscous fluid is ALWAYS easier to move. (Air is a fluid.) And since less mass will fit in a given volume when the temperature is increased, the engine sucks in less on the intake stroke, further reducing pumping losses.

You mean like the quote I just highlighted in red? Come on o.p., I just listed my reasons stating the opposite. Guess my explanation has no value to ya. There are pleny of things that could worsen your gas mileage more than a CAI.

Hope you're not questioning me, cuz if you are, we're gonna need to take this outside, (This thread, I mean) Bub. lol! :D

The burden isn't seeing the term... It's looking at your tail-pipe. Don't know what you meant by saying that. Your response also has that tone of nerd-rage against tuners and one who also lacks a math/science background. I'm starting to get the feeling that open-mindedness is a virtue.

Back pressure does not exist in logical terms. That's exactly what I meant by it.

Literally, back pressure would describe a force which was pushing exhaust back up the exhaust channel, which does not occur. In reality, what most people refer to as "back pressure" is the slowing of the flow of exhaust gasses due to over cooling/over expansion.

It's a burden on my mind to see that yet another person who appears to have some grasp on the engine as a whole is using the term back pressure as though it actually means something that applies to engines, when in reality it does not. A more accurate term would be flow restriction, and that doesn't fully encompass the circumstances either.

I had to look up "adiabatic" in the dictionary. No match found. I see what you mean by "soaking" the metal by way of the intake charge. Don't worry about losing precious heat with cooler air because the combustion chamber will inevitably heat up. Pressure in the engine bay will keep hot air around the motor, too. You're telling me that an already warm engine will be a more ideal environment for combustion than a cooler one. Sucks for my MPGs, it's cold outside! That explains why this demographic has such a high demand for engine block heaters. I thought it was compression or spark plug location that affected thermal-effeciency. (The term you clarified, but didn't specify.) Swapping in a CAI/SRI also reduces mechanical effort along with more HP. There's no use in keeping the intake system hot. The coolant is in charge of keeping the head at the temperature it needs to be, not the outside air.

Not trying to be a smart-ass, but I'd like to see a link to one of those studies.

Oh it doesn't happen? Well, I'm not referring to the slowing of exhaust flow, I'm talking about recirculation of spent gasses. Wait... So that means that backpressure does exist! :eek:

Hope I'm not truly burdening your mind, because you're not burdening mine.

I think I spelled it incorrectly - here's an explanation:

define:adiabatic - Google Search

I used the term somewhat incorrectly - I should have said that a perfectly efficient engine is adiabatic. You'll see why once you read the definitions listed.

I should probably start saving those links as I come across them. Someone here will provide one at some point, I'm sure.

Good word choice.

That's cool dude, don't sweat it. They don't have spell check on these message boxes. :p

No links? You must be expecting me to bash you for it, but like I said, don't worry about it. I'm gonna look into that WAI thread and see for myself.

So you're talking about EGR flow? (Rhetoric.)

What you're suggesting is that the exhaust is drawn back into the cylinder after having exited, which isn't true. What actually happens is that as the exhaust exits the engine, pressure in the exhaust channel builds as the flow slows, due to expansion and cooling, and this prevents the scavenging effect that you feel is so necessary.

Of course, I'm sure it never occurred to you that some automakers have actually designed engines with this in mind, because it's more efficient to just leave some of the exhaust gasses in the cylinder than to recirculate them via EGR flow... Of course, if there is exhaust gas left in the cylinder, that would reduce the dynamic displacement of the engine, meaning that less fresh air is drawn in, thus less fuel is necessary to maintain the same AFR, and a higher throttle angle must be used to generate the necessary amount of power to maintain the vehicle's speed, reducing pumping losses.

Do you have any links or data which backs up your claims?

I wasn't expecting flame-age for not having links readily available, but I really should start keeping a file of them. I often give information that could be covered by them, but can't provide the link for a point of reference. It's a bad practice that I need to break.

Believe it or not, a CAI can have a cooling effect on the engine.

Imagine what happens when you drink cold water. The first process for you to metabolize the water (as if there were such a thing) is for your body to bring that water up to temp. That takes energy, does it not? Some of that energy could have been used as propulsion, rather than wasted as heat in order to bring the air up to temp for combustion.

That's about the easiest way I could explain it.

It is the thermostat's job to open and close to maintain a specific temperature range within the engine, but the coolant's job is to extract heat, not provide or insulate it. The air temp is important in this respect, because colder air will also pull heat away, and since combustion provides heat to the engine, part of the heat that would normally be given to the combustion chamber is then given to the air.

You did not just bag on my rhetoric... Nobody disses my rhetoric. :cool:

My statement was taken out of context, by yours truly.

And then you dare say that "it would never occur to me" that "some," but not "all" automakers (Wonder who those are.) ensure that gasses don't recirculate into the cylinder. That's not the cause of the problem. It hasn't occured to you that I was, in fact, placing the blame on a lousy exhaust pipe design. At no point did I mention the EGR.

I do, as a matter of fact. Because I don't wanna go link hunting at this hour, I'll give you the publication "How to Build Nissan Sport Compacts" by Sarah Foster as a source of my info.

Uh-huh and a warmer intake charge "can have" a warming-effect.

You're not gonna burn many calories by drinking cold water. Energy in the muscles are in the form of ATP, so losing a couple of calories isn't taking anything away from what you have and not all of what you just consumed will be utilized either. Using your analogy to support my claim, drinking a lot of hot water will also make the body work to regulate its internal temperature. That too, takes calories, but you're losing electrolytes in the process of it. (Opening of the pores to relieve the body of excess heat) A CAI/SRI reduces the mechanical effort it takes for the engine to ingest air and has the benefit of increasing HP. Running your car at summer temperatures will have a negative effect on performance. Gasoline at too hot of a temperature will evaporate, which I haven't heard you mention. So if you heat the air/fuel mix too much, you end up with less energy from the loss of matter. (Gasoline) That's not the most fuel-efficient way to go. I'd rather go with a CAI/SRI achieve the goal of better MPGs and getting more HP along the way than running my engine too hot, inevitably engaging the cooling fans and once again, putting more a strain on the engine. Not to mention the possiblity of evaporating those precious mists of fuel the injectors spray out.

It may not specifically work to heat the engine, but it's dependant on it. And at the temperature that the cooling system operates, heat will be transferred and distributed throughout its pathways, maintaining a consistent temperature. Conversely, if heat is drawn away from the engine and to the coolant, so that too creates a cooling effect which wasn't accounted for in your response.

Anyone mind if i take a swing at this one since I'm the performance guy and this is the exact type of driving i was sayin my mods help for?

By all means, take the stage. -_-

(If I may say so myself...)

OK FIIIRST OF all by reading the fact that your OLD car used to lift at about 100 you are NO stranger to speed.
Also you're young and kinda stupid (daring if you prefer)
Don't worry I am too
I'm just gonna give you the recepie that i give all of my friends ... They drive pretty much like you

Firstly seafoam the car and change the oil. this'll run you about 30 bucks get some 5w 30 preferably

Second Stop running that thing on cheap gas You're a teen so i know you are.. Run it on some shell V power to clean out that top end and make it burn the way it should (higher octane in cheap motorss like that often helps quite a bit with power. 20 cents per gallon pays itself off

Third K&N OR Spectre Cone filter Some will say you lose power from this but You know it isn't true You can HEAR the extra power and FEEL that extra snappiness, well guess what that's a lie It MAY help you with fuel economy (because it has a similar effect to the WAI) however the power you FEEL is actually just the car responding to the throttle snap much quicker Heat soak and pullling warm air in will decrease power
So what i'd ACTUALLY suggest doing go to autoanything.com.. that's where i get em and buy yourself a K&N air filter then delete your intake resonator if you have one
You'll still get the sound but it should be a whole lot more affective with power actually Around $40

Forth you can't stand how it sounds Go to ebay find yourself a flowsound 2 chamber muffler KEEP YOUR RESONATOR ON or that will be raspy as hell like a fart-canned civic. may not help with gas buuuuut you wont have to drive as fast to hear the sound of the motor. $40

Inflate your tires to the max pressure or as near as you dare to go to it, tirre manufacturers actually underrate their tires just for saftey reasons. This'll give you less rolling resistance and drag at high speed ;) Free

and lastly TAKE OUT WEIGHT ditch unnessecary stuff if you dont drive 4 people around ditch the back seat > Your spare tire and spare tire jack can be removed and get a can of fix a flat that should cover you if you get one. also any extra crap that reeeeeally doesn't need to be in your car Remove it Free

Oh and lastly delete the spoiler if you have one and wash the car At the super high speeds youre traveling this may actually help Free

For most people on this forum these mods are useless but for you i think they may actually turn out great. Lemme know the results

Ok mr stereo type lol. FWI, I sea foamed the oil ad gas the first week I had it and left the oil in for 300 miles (never going above 3k rpms) and then changed to royal purple 10w-30. My tires are brand new and I had the car aligned, and I wash my car AT LEAST 2 times a week, And I wash the undercarriage too ( I would spend $20 a week keeping my old truck clean). I havent run any of my 8 past cars on less than 93 octane. And there is no clutter in my car lol. And yes im 18 years old. My intro thread shows my history of cars and why I ended up here.

On the subject of the CAI, I may just go to a better filter and keep the stock intake because of that annoying droning sound coming from a stock engine with a CAI.

Well then most of the stuff i told ya to do you already did helps doesn't it:thumbup:

along with that I'd suggest a K&N filter or a Spectre filter in place of the stock filter since you want the stock intake I prefer K&N personally still take the intake resonator out though gives it a nice little growl when you wanna open it up

oh and since your tires are new and always kept aligned make sure to keep all of the tires at or as near as max pressure as you dare Lots of guys on here have had sucess with this increasing FE
You gotta realize all the guys here learn to live with eachothers ideas
And don't take any of it personally haha i just havent had the chance to post a sarcastic post on here yet

none taken lol. But yes I already new this. I run them at the recommended pressure so I can handle on the back roads without skidding into a ditch.

Haha good idea man Try out that K&N or the spectre if you prefer it's half the price. But i like having the backing of a milllion mile warranty from K&N and in all of our cars they've gone 45 thousand to 55 thousand miles before needing to be cleaned

I have zero problem with people who like speed spending time here talking about efficiency. The amount of cross-over between the two interests isn't insignificant. (I've spent many days at various tracks for fun... no, never with the Firefly)

But I'd prefer it if the speed-only related chatter is saved for the other speed related forums.

This isn't directed just at you, Domman56. I'm just asking, in general, that people consider: if the post isn't about efficiency, save it for somewhere else. There are so many other forums that want to help you burn more fuel. This isn't it.

Oh i know metro i was just reffering to this that he had posted in the first page
" Now im not hardcore about mileage, I still go full throttle on a regular basis "

So I was just saying the intake resonator since it is a free thing to do and he goes full throttle anyways

ChillyBear, I've been there and done that. Currently I have a Zetec powered ZX2 and my wife drives a Zetec powered Focus wagon. Both are ATX. Check out my gas log to see what a Zetec can give you if you decide to control your right foot. Also check out my mods. I can say that all of my performance mods combined don't add up enough benefit to outwiegh the three aero mods I've done: Grill Block, Air Dam and Rear Fender Skirts. Additionally the aeromods cost me about $50 total. The performance mods, well I'm emberaced to say how much they cost. The only benefit from the performance mods is if the mods help torque at very low rpm, less than 2K, then you can pulse for a shorter time before you glide. I'd say my performance mods help me in this aspect because I can not force my ATX to shift under 2K, so I can accelerate quicker up to the pulse speed. If your driving 80 miles of highway, I also do, then Aeromods will be a BIG bang for your buck. I'd recomend doing them first.
Specfics for the Zetec and Focus. The Focus is already a CAI and in fact it is also a Ram Air. I'd cut off the Ram Air hose and clamp a piece of dryer duct on it so it can pull air off of the header heat shield, this will help. For a slight bump in torque, you can get the exhaust cam from a ZX2 Zetec for almost free from TeamZX2.com. The resonator on the Focus Air box is a non issue, no need to remove it, additionally the stock air box and intake tube are very good, no need to buy an aftermarket one for FE. The Focus sit's realy high, lower it and put some pizza pan wheel covers on for Aero. The Focus can probobly benefit greatly from a front belly pan, behind the bumper is very open. Also, what model do you have? 2dr, 4dr, Wagon? Additionally, I love my block heater! get the Ford one, the aftermarket ones from Kat's fail and don't fit well. The Ford one fits easy and even though it's only rated at 400w and the Kats at 600w, the Ford one works just a quick. I also have an oil pan and trans pan heater, the Kats adhesive backed one. Combined they have benefited me by as much as 3-4mpg this winter.
With the mods done to my ZX2 I can cruise at 50mph and easily average over 50mpg. In my gas log you'll see a trip of 653 miles where I got 50mpg and another 427 miles where I got 54mpg. I also easily surpass 30mpg city. Keep in mind I try not to exceed 55mph on the highway and coast a lot in the city and highway. As already mentioned, driving better will yeild the greatest benefit.
Something to consider: I have about every bolt on mod availble for the Zetec and all my parts are considered the best available for the ZX2 or Focus Zetec. My FE is better than almost all ZX2's I've heard of (only two that I've seen that have beaten 54mpg) and I'm ATX, they are MTX. My ZX2 also holds the Quickest Naturally Aspirated ATX ZX2 time in the 1/4 mile. 15.697 at 88.51mph (I know it's not really that fast, kinda like being the fastest Turtle). I don't see the performance mods hurting my mpg, they are very expensive and are probably a wash in the long term scheme of mpg.
With better aero, Lrr tires and little lean burning, I expect to average over 50 mpg when I am now averaging 42 mpg on my commute.
I've rambled enough, there is more to say, but maybe another time.
Hope this helps!

Tygen, does the zx2 exhaust cam's year or transmission make a difference for fitting on mine? I know some cars have different cams for different transmissions. This is a VERY good tip by the way. Thanks, I just wonder if I will need to reprogram my computer for this or not.

Mine is a 2004 zx3 with a 5 speed. I agree with the earlier post that this forums isn't for performance. Which is fine, I go elsewhere for that stuff, and in reality my car is fine for back roads where little power is needed, Im probably going to do the "invisible" aero mods because looks of a car a truly more important than a 2mpg gain. Ill most likely do the underbody and possible grill mods, along witht he block heater. I havent figured out my mileage, but I really just want to lower my highway mileage because I don't have the discipline to keep it under 2k rpms in the city, I do 2.5k most of the time to keep the little shift arrow from lighting up on the dash. But I know that next year in college im going to be strapped for cash so that may change.

skirts would look G on that ford

-AY
I prefer not to do skirts. anyways, I JUST BOUGHT mudflaps for the car because there is alot of dust out here in the boonies where I live. Driving a dark car sucks sometimes.

Heres some pics of my CLEAN old cars. That truck was badass, and you get to see the carnage the deer caused to my slaab.
http://s301.photobucket.com/albums/nn41/corvairkid17/

For the Cam, the year does not matter, neither would the transmission, however the Lower Engine Cradle is different betweent the Focus Zetec and ZX2 Zetec, so you'd have to swap a bunch of stuff over that would not make it worth while. I believe the ZX2 cams would be considered a "Stage 1" cam for the Focus. I believe the only difference is a small amount of lift and duration.
Tuning would help no matter what, more ign. advance and such always helps. I'd highly recomend trying the Air dam as well as the grill blocks. Don't be ashamed :)
Invest in the ScanGauge II and learn to drive better and you will be rewarded far more for that investment vs. all the others. When your ready to really push the limits....let us know :D